An agent that binds to but does not activate alpha-adrenergic receptors thereby blocking the actions of endogenous or exogenous alpha-adrenergic agonists. alpha-Adrenergic antagonists are used in the treatment of hypertension, vasospasm, peripheral vascular disease, shock, and pheochromocytoma.

An agent that binds to but does not activate alpha-adrenergic receptors thereby blocking the actions of endogenous or exogenous alpha-adrenergic agonists. alpha-Adrenergic antagonists are used in the treatment of hypertension, vasospasm, peripheral vascular disease, shock, and pheochromocytoma.